Direct Electropolymerization of Copolymer Electrolyte into 3D Nano-Architectured Electrodes for High-Performance Hybrid Li-ion Macrobatteries

Abstract

It is shown that electropolymerization can be addopted to deposit a a copolymer electrolyte (PEO-PMMA) into titania nanotubes for the fabrication of on-chip microbatteries. The copolymer embedded TiO2 nanotubes shows good electrochemical performance, which is due to the electrode/electrolyte interface achieved by filling the nanotubes with the copolymer. The titania nanotubes and the copolymer-embedded nanotubes are characterized by surface analysis techniques including (SEM, EDX, FTIR and XPS). This electrolyte deposition process can be extended to any kind of 3D nano-architectured electrodes. The electrochemical performance was evaluated in lithium test cells.

Electrochemically Controlled Deposition of Ultrathin Polymer Electrolyte on Complex Microbattery Electrode Architectures

“…14,16 Djenizian et al demonstrated the direct electrochemical polymerization of polyethylene oxide-b-methylmethacrylate co-monomer electrolyte from 0.035 M aqueous LiTFSI solutions onto 3D nanostructured electrodes. 28,29 It should be noted that most of the electrografted films were electrochemically polymerized from monomer solutions where radicals generated from the respective solvents (or from oxygen saturation) 26 initiated the polymerization as opposed to radicalization of the unsaturated functionality of the monomer reported by Jérôme et al 22 Herein, we present our approach for electrochemical grafting and polymerization of ultrathin polymer electrolytes (UTPE) onto 3D cylindrical micropillars and also onto planar disc electrodes from ternary monomeric electrolyte blends in the absence of sacrificial solvents. These blends consist of a poly(ethylene oxide)acrylate block co-monomer, a pyrrolidinium imide ionic liquid (IL) and a lithium imide salt.…”